1. Field of the Invention
This invention relates generally to preventing the build-up of snow and ice on the lower portion and edge of a roof and in particular to heat strips for roofs that fit under existing or new shingles and are not easily seen from any view of the roof.
2. Description of Related Art
In roofs located in cold climates where there is an accumulation of snow and ice, ice forms at roof margins during the winter and then the ice overhangs the edge of the roof forming icicles and backs-up into soffit vents. The ice forms dams on the roof itself and continues to build in size as the snow melts from further up the roof. These dams hold the water from running off the roof's edge. As the water builds it works its way under the shingles above it. Once the water makes its way under the shingle, the water drips into the attic space damaging insulation, wall boards, ceilings, and any building materials below. Solutions to this problem have included heat strips made with wire which are attached to the outside of shingles in a zigzag pattern resulting in not only a rather unsightly appearance but also it is only efficient at these drip points or the point of the heating wires closest to the roof edge.
U.S. Pat. No. 2,699,484, issued Jan. 11, 1955, to Hebert L. Michaels, discloses a de-icer for roofs comprising a hollow shingle-shaped casing forming an extension of a roof and attaching to the trim boards of the roof and having an electrically conductive conduit in said casing. However, this de-icer changes the appearance of the roof line.
U.S. Pat. No. 3,691,343, issued Sep. 12, 1972, to Victor B. Norman, discloses a modular system of sheet metal de-icing shingles and valley sections for preventing the build-up of ice at the eaves of a roof having fine heater-wires arranged in a trapezoid configuration on the under surface of the shingles. However, this modular system presents an unsightly appearance of the roof on a house.
U.S. Pat. No. 4,769,526, issued Sep. 6, 1988, to Tony F. Taouil, discloses a roof de-icing panel which also replaces one or more lower courses of shingles. It includes a perforated metal portion extending from the gutter to prevent debris from clogging the gutter, but it does not melt water flowing into it. Also, the roof deicing panel changes the roof edge appearance.
U.S. Pat. No. 5,391,858, issued Feb. 21, 1995, to David R. Tourangeau discloses an ice dam melting system in the form of a hollow heat cell panel which replaces the last course of shingles at the edge of the roof, a conduit supported by the lower panel, an upper panel formed of metal and connected to and supported by said conduit, and a heat-generating mechanism in the conduit. However, this system changes the appearance of the roof edge.
U.S. Pat. No. 5,786,563, issued Jul. 28, 1998, to Anita Tiburzi, discloses modular ice and snow removal panels with gutter exclusion valves for removing snow and ice and which includes a series of panels aligned in end-to-end fashion along a roof eave and atop the edge rows of shingles. The panels each include internally arrayed beating elements and an electrically operated valve element proximate a lower edge for the purpose of channeling melted ice and snow either into or over a conventionally secured gutter. However, such modular ice and snow removal panels change the appearance of the roof on a house.
U.S. Pat. No. 6,166,352, issued Dec. 26, 2000, to Kenneth Turton, discloses an ice shield for eaves of a roof comprising at least one continuously wound roll of a flexible and elongate mat of material which includes a first exposed face and a second reverse side face. The elongate mat is constructed of first and second layers of a durable rubberized material capable of convecting heat generated by generally longitudinal extending coils embedded between the layers. An adhesive coating is applied to the reverse side face and covered with a release tape. The mat is unrolled and positioned atop and along an eave edge location of the roof. The ice shield is installed underneath one or more initial rows of shingles to melt ice deposits. However, on existing homes, shingles have to be removed to install the mat, and in many cases it is necessary to match the shingle color due to aging which may be difficult. A professional roofer is generally required to perform the installation of such a mat, not a handy homeowner.